This is a 2/0 AWG stranded connector with a 3 inch body and a 0.91 in (23 mm) O.D., that are for splicing applications on aluminum or copper cable products
The 3M™ Connectors CI Series are for splicing applications on aluminum or copper cable conductors. The connectors CI Series aluminum are specially designed for use with 3M™ Pre-molded Power Cable Splice Bodies QS-I, QS-II and QS-III. These connectors meet the requirements of ANSI C119.4.